201220121231 has 4 divisors (see below), whose sum is σ = 201448004472. Its totient is φ = 200992237992.

The previous prime is 201220121177. The next prime is 201220121287. The reversal of 201220121231 is 132121022102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 132121022102 = 2 ⋅66060511051.

It is a cyclic number.

It is not a de Polignac number, because 201220121231 - 2¹⁰ = 201220120207 is a prime.

It is a super-2 number, since 2×201220121231² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201220721231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113940296 + ... + 113942061.

It is an arithmetic number, because the mean of its divisors is an integer number (50362001118).

Almost surely, 2^201220121231 is an apocalyptic number.

201220121231 is a deficient number, since it is larger than the sum of its proper divisors (227883241).

201220121231 is an equidigital number, since it uses as much as digits as its factorization.

201220121231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227883240.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 201220121231 its reverse (132121022102), we get a palindrome (333341143333).

The spelling of 201220121231 in words is "two hundred one billion, two hundred twenty million, one hundred twenty-one thousand, two hundred thirty-one".